Damper.



0. J. FRANCIS.

DAMPER.

APPLICATION FILED JAN. 13. 1916.

1L ,2]. 9 1 U2. Patented Feb. 13, 1917.

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OMAR T. FRANCIS, OF READING, PENNSYLVANIA.

DAMPER.

Specification of Letters Patent.

Patented Feb. 13, Matt,

Application filed January 13, 1916. Serial No. 71,814.

To all whom it may concern:

Be it known that I, OMAR J. FRANCIS, a citizen of the United States, residing at Reading, in the county of Berks and State of Pennsylvania, have invented certain new and useful Improvements in Dampers, of which the following is a specification.

My invention relates to damper mechanisms comprising the usual interiorbutterfly damper plate and a connected sliding plate covering a wall opening; and it consists in improved operating connections between the rotating and sliding plates whereby the plates are automatically retained in any jointly adjusted position, against unintended movement. The invention is fully described in connection with the accompanying drawing and is specifically defined in the claim.

Figure 1 is an elevation of a stove pipe section having my invention applied thereto.

Fig. 2 is an end view of same; the respective planes in which the flexible rotary crank arm and sliding-plate link naturally swing being indicated by the disconnected positions shown in dotted lines.

A represents a section of ordinary cylindrical stove pipe in which is mounted the usual butter-fly damper B. The end portion 2 of the diametrally mounted axle 13 of this damper B, extends beyond the wall of the pipe and has fixed thereto a flexible crank arm 3, adapted to swing in a plane 4-, indicated in Fig. 2.

The pipe is also provided with a wall opening 0, located above and to one side of the rotary damper axle 13; which opening may be closed to any desired extent by an exteriorly mounted vertically slidable damper plate 5, having guide slots 6, 6, 6 loosely engaging securing posts or screws 7, 7, 7 fixed to the pipe as indicated. The slidable damper plate is provided with a pivot post 8, located about midway of the width and length of the plate; and this post is formed with a flat seating shoulder 9 for a flexible connecting link 10 which is pivotally mount- Goples of this patentmay be obtained for ed upon said post so as to normally swing in a plane 11, indicated in Fig. 2.

It will be seen that the swinging plane 4: of the rotary damper crank arm 3, is oblique to the swinging plane ll of the sliding dam per connecting link 10. in connecting the flat free end portions 3, and 10 of said arm 3 and link 10 as shown at 12 to effect the joint movement of the rotary and sliding dampers, both the crank arm and link will thus be strained out of their normal shape, as permitted by their flexible form indicated; and a tensioning effect will be thus produced which provides a constant limited resistance to movement of the dampers such as will insure an easy and uniform operation of the parts and at the same time be suflicient to automatically prevent any un intended shifting from any adjusted position. Thus the need of any locking means for retaining the parts in adjusted position is dispensed with, and a smooth easy movement secured, with a very simple and inexpensive construction. A. button is preferably provided on the end of the sliding-plate pivot post 8 for convenient handling.

What I claim is:

In combination with a cylindrical stove pipe having an interior rotatable damper plate with a diametrally arranged pivot axle, and a wall opening located above and to one sideof said axle; a damper plate for said opening longitudinally slidable on the pipe and provided with a pivot post, a flexible crank arm exteriorly fixed to said pivot axle, and a flexible link connecting the free end of said crank arm to said pivot post; said link being arranged to swing'in a plane out of parallel with the planein which said crank arm swings and said pivoted parts being placed under tension whereby the sliding damper is retained in adjusted position.

in testimony whereof I aflix my signature.

ONAR J. FRANCIS. Witnesses:

WM. F. WEBER, HENRY S. BERNHART.

five cents each, by addressing the Commissioner of Patents, Washington, D. 0. 

